A venturesome research project is proposed to develop the tools needed to create transgenic quail embryos. The techniques of transgenesis in the mouse embryo are largely responsible for the dramatic recent progress in the molecular genetics of vertebrate development. Avian embryos are selected because they are accessible to study at all stages of development without the heroic efforts that are required to study mouse embryos. Because of these advantages, the major system for classical work in the developmental and cell biology of higher vertebrates was the chicken. Here we propose to begin the refinement of molecular genetic tools that are heretofore only available in the mouse onto the quail embryo. The quail offers advantages in the small size of its egg, the moderate size of the breeding adults, and its short generation time. Because of these advantages, the proposed work will allow molecular genetic experiments on a higher vertebrate embryo both more rapidly and less expensively than comparable work on the mouse. Our overriding goal is to combine transgenic quail technology with the use of two-photon laser-scanning microscopy, so that transgenes containing the coding sequence for the green fluorescent protein (GFP) can be used to follow gene expression patterns in living embryos. We will use HIV based vectors, which have been shown to efficiently generate murine transgenics without being silenced and maintaining endogenous gene expression, to insert the GFP expressing transgenes within the egg of the developing avian embryo. Although ambitious, the project builds from ongoing work in the laboratory on avian development, optimized viral vectors for vertebrate embryos and quantitative microscopy of living avian embryos. These ongoing efforts provide the fertile ground needed for the transgenic avian project to succeed. [unreadable] [unreadable]